The embodiments described herein relate to a magnetic resonance imaging apparatus and program, and an RF pulse transmission method.
A magnetic resonance imaging apparatus can acquire a tomographic image of a subject by generating magnetic resonance signals using nuclear magnetic resonance phenomena.
An image data acquisition method used in magnetic resonance imaging apparatuses has been known in which the order of slice plane excitation is specified for multi-slice acquisition performed to acquire many sequential slice planes. In the method, to be concrete, the order of slice plane excitation is specified such that, while slice plane excitation is repeated at a constant period, selection is done such that slice planes are not adjacent to each other for consecutive excitation. This is to realize high-speed data acquisition while suppressing interference between nuclear magnetic resonance signals from mutually adjacent slice planes so as to prevent image contrast deterioration. (See Japanese Unexamined Patent Publication No. Sho 63 (1988)-9432, for example.)
However, even in cases where, as in the above known method, selection is done such that two slice planes are not adjacent to each other for consecutive excitation, using non-rectangular RF pulses which allow side lobe generation causes a slice plane being excited to be affected by overlapping side lobe excitation at adjacent slice planes. This results in non-uniform signal intensity between slices.